Second certificate, which is a localhost self-signed one

[Murzoo]

Hi,

I'm new to the NPM. I've just set up an instance at home, and I've moved over an existing nginx proxy setup. Everything works fine, but one thing.
When I scan my site with ssllabs for example, it is saying I provide two certificates. One which is the correct one for my dns name, and a second one which is for localhost and is also self-signed.
Why do this happen? Any ideas?

Thanks!